Mrs Moore, the judge added, had "unfairly portrayed Stephen as a violent and difficult son who made her and Roger's life a misery."

She simply "refused to accept" that Roger's "unchanging intention", while he had all his mental faculties, was "to see Stephen at the helm".

By 2009, Roger was suffering from serious memory loss and his increasing sense of uselessness led him to say "I might as well shoot myself", the court heard.

But, as Stephen grew up, his father had encouraged him to work on the farm and passed on to his son his "passion for farming".

Spending three years at agricultural college, Stephen had "thrown himself wholeheartedly into working on the farm".

"Since he was a teenager it was not only clear to him that he would one day take over the running of the farm, but also that Roger... encouraged him in that belief", said the judge.

"Roger would say to him that all of this, referring to the farm, would be his one day. It seems to me that everything points to an over-arching plan under which Stephen would inherit the whole farm and business in due course and that Stephen was told this was the case."

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Mr Moore changed his will in 2012, disinheriting Stephen of the farm, but the judge said that, by then, he was "playing very little part in events".

Mrs Moore described her son's behaviour as "intolerable" and accused him of "molesting" Roger, "by way of violence, threats, pestering and other forms of harassment".

Mr Moore had at one point even sought a non-molestation order against his son, it was said.

But the judge described Mrs Moore's accusations of bad behaviour against her son as "so trivial as to be of no effect".

He added: "Roger, in his right mind, would never have contemplated litigating against his own son. Matters between father and son were nowhere near the kind of total collapse described by Pamela and other members of the family.

"Roger would have been appalled at the family's private affairs being exposed to public scrutiny and at the prospect of the farm being split up."

The judge said of Stephen: "He clearly loves his father and has always looked up to him.

If I were to cash in I would be a very wealthy man, but I have no intention of cashing inStephen Moore

"By contrast, his relationship with Pamela has always been a difficult one... sad to say, relations between them had been difficult since Stephen's childhood."

Stephen, he said, had worked on the farm since childhood and now "in effect runs the farm, as Roger is too ill to participate".

Starting off on just £200 for a working week of up to 50 hours, he was still earning less than £300-a-week after becoming a partner in the business.

He only did all that because "he truly believed, as he had been encouraged to believe, that in the fullness of time he would inherit the farm and the business".

The judge added: "The fact is that promises were made, and in reliance on them he devoted his entire working life to the farm and the business."

He could not pursue an alternative career because of his "whole-hearted commitment to the farm".

Stephen told the court: "If I were to cash in I would be a very wealthy man, but I have no intention of cashing in. If we have a good year, we might be able to afford a holiday or a new car, if not then so be it."

Judge Monty ordered that the farming partnership between father and son should be dissolved "because of Roger's ill health".

Mr Moore's share of the farm will be transferred to Stephen, although his parents can continue drawing an income and living in the farmhouse for as long as they need to.

The judge concluded: "This is a just and equitable outcome. It honours what Roger always intended.

"It means that the farm can continue to be farmed by the next generation of the Moore family as Roger always intended."